Absolute Value in math

Please tell me how to do it PLEASE!

1.If x > 1, then x - | x - 1 | = ___
a) 2x - 1 b) 1 - 2x c) 1 d) 2x = 1 e) -2x - 1

if x>1 then |x-1| = x-1 ==>
x- |x-1| = x-(x-1)=x-x+1=1
Answer is (c)

| x - 1 | =x-1 when x ≥ 1
| x - 1 | =1-x when x < 1

x - | x - 1 | =x-x+1=1